One aim of modern diagnostic medicine is to better identify sensitive diagnostic methods to determine changes in health status. A variety of diagnostic assays and computational methods are used to monitor health. Improved sensitivity is an important goal of diagnostic medicine. Early diagnosis and identification of disease and changes in health status may permit earlier intervention and treatment that will produce healthier and more successful outcomes for the patient. Diagnostic markers are important for prognosis, diagnosis and monitoring disease and changes in health status. In addition, diagnostic markers are important for predicting response to treatment and selecting appropriate treatment and monitoring response to treatment.
Many diagnostic markers are identified in the blood. However, identification of appropriate diagnostic markers is challenging due to the number, complexity and variety of proteins in the blood. Distinguishing between high abundance and low abundance detectable markers requires novel methods and assays to determine the differences between normal levels of detectable markers and changes of such detectable markers that are indicative of changes in health status. The present invention provides novel compositions, methods and assays to fulfill these and other needs.